> I want to rank my friends, be part of different social circles, because that's how I operate. That's actually a really good point, you've hit the nail on the head with that one.
Manually implemented something like this in my fbook account, but it was a major pain to do and doesn't provide all of the proposed functionality/openness.
It would ruin much of their "walled-garden" strategy to let this work with other services. What they believe is their strength, will become their weakness.